← Back to dex
Rare variable star 39 EP

HD 229680

RA 282.6155° · Dec 15.9402° · star

Loading sky survey…
🌌 View in 3D star map
Tonight’s visibility

Computing the sky for your location…

Score breakdown

· 5 badges
39 pts · Rare
Rare 50 pts → Epic
  • Supergiant +18
  • Strongly variable +10
  • Variable star +5
  • Yellow-white F-type star +3
  • A named variable star +3
Total score 39

11 more points to reach Epic.

Badges

  • Variable star · +5
  • Yellow-white F-type star · +3
  • Supergiant · +18
  • Strongly variable · +10
  • A named variable star · +3

Trivia

Hard to believe

  • True brightness. It pours out about 394.5 thousand times as much light as the Sun. It only looks ordinary because it is so far away.

What it actually is

  • Spectral class. Its spectrum reads F5Ib-II — an F-type star — a little hotter, whiter and shorter-lived than the Sun.
  • Where it is in life. It is a supergiant, hundreds of times wider than the Sun.
  • It changes. This star does not hold still: its brightness rises and falls on a rhythm of hours, days or years, either pulsing in size or being eclipsed by a companion.

Find it in the sky

  • How to spot it. At magnitude 10.8 you'll want a small backyard telescope, over in Hercules.
  • Northern sky. It rides the northern half of the sky — an easier target the further north you are.
  • Best time of year. It stands highest in the middle of the night around July — that's when to go looking.

Its true colour

  • Its true colour. Measured through blue and visual filters it comes out yellow-white (B−V 0.4) — a shade brighter and crisper than our own Sun.

Properties

absmag
-9.16
bv
0.387
constellation
Her
luminosity
401790.8108
mag
10.84
name
HD 229680
spect
F5Ib-II
var amplitude
0.76
var designation
AP
var max
10.439
var min
11.199

About HD 229680

HD 229680 is a rare variable star. It sits in the constellation Her, shines at apparent magnitude 10.84 and has spectral type F5Ib-II.

Its spectrum reads F5Ib-II — an F-type star — a little hotter, whiter and shorter-lived than the Sun.

How to see it

Look for HD 229680 in the constellation Her. At apparent magnitude 10.84, a small backyard telescope will bring it into view.

Like any astronomical target, HD 229680 is best seen from a dark site away from city lights, and when it is above the horizon depends on your latitude and the time of year. The visibility panel above works out tonight's viewing window for your saved location.

Why HD 229680 is a rare variable star

HD 229680 scores 39 points on Spacedle's rarity scale, which places it in the rare tier. Another 11 points would lift it into a rarer tier.

That score comes from 5 science badges — Variable star, Yellow-white F-type star, Supergiant, Strongly variable and A named variable star — each earned for a real, measurable property of the object. Rarity on Spacedle is never random: the more remarkable an object's astrophysics, the more badges it collects, the higher it scores, and the rarer it ranks.